[The sheath of Scarpa ganglion cells in the baboon Papio papio].

The sheath of the bipolar perikarya of the vestibular ganglion (Scarpa) in Papio papio is made up of several Schwann cells which concur to form loose myelin, and at most five layers of compact myelin. Most of the Schwann cytoplasmic layers stop at the emergence of both neurites, forming at the point an incomplete Ranvier half-node. The constitution of the vestibular perikaryal sheath in Papio is intermediate between those previously described in the Rat and in the Human.